activeadmin: Batch Action greyed out and not working

I’m using the latest version of Active Admin (gemfile leads to gem “activeadmin”, :git => “git://github.com/gregbell/active_admin.git”) and in my Active Admin site, the Batch Action option is showing. However it’s greyed out and it’s not set to false in the config file. I tried to add a batch again to my mode programs:

batch_action :save do |selection|
  Program.find(selection).each do |program|
    program.save
  end
end

But that’s not showing up either and I’m not sure if it’s the right syntax (the :hot confuses me). Does anyone know how to fix this?